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Öğe Azo-azomethine based palladium(II) complexes as catalysts for the Suzuki-Miyaura cross-coupling reaction(Elsevier, 2020) Sunbul, Ali Burak; Inan, Ayse; Kose, Muhammet; Evren, Enes; Gurbuz, Nevin; Ozdemir, Ismail; Ikiz, MesutSeven azo-azomethine ligands (2-8) have been synthesized from the reaction of (E)-5-((4-chlorophenyl) diazenyl)-2-hydroxybenzaldehyde with different aniline derivatives. Ligand structures were characterized by the combination of IR, UVeVisible spectroscopy, C-13 NMR, H-1 NMR and elemental analyses. The mononuclear Pd(II) complexes of these azo-azomethine compounds were prepared with sodium tetrachloropalladate(II) and characterized. According to the UVevisible, FTIR, elemental analyze and HRMS data, the Pd (II) complexes 9-15 are formed by the coordination of N, O atoms of the ligands. Solid state structures of 2, 6 and 7 were determined by single crystal X-ray diffraction studies. Also, Pd(II) complexes were used catalysts for Suzuki-Miyaura coupling reactions of phenylboronic acid with aryl bromide in aqueous media. When the catalytic studies were evaluated, it was found that all of the complexes were suitable for the Suzuki-Miyaura cross-coupling reaction. (c) 2020 Elsevier B.V. All rights reserved.Öğe Dimetilasetal fonksiyonlu benzimidazol-N-heterosiklik karben kompleksleri: Sentezi ve özellikleri(İnönü Üniversitesi, 2025) Evren, Enes; Özdemir, İsmailSon yıllarda amit bağlarının; yeni, atom-ekonomisi, katalitik sentezlerinin geliştirilmesi, günümüz yeşil kimyasına uygun çevreye zararsız katalizörlerin sentezlenmesinde incelenecek yollar ve tepkimelerin işleyiş mekanizmalarının araştırılması ile ilgili çalışmalar önem kazanmıştır. Amit bağı kimyadaki en önemli fonksiyonel gruplardandır. Enzimlerde peptid bağlarının oluşumunda, farmasötik moleküllerde, zirai kimyasallarda ve doğal ürünlerde mevcut olan bir gruptur. Amit bağ oluşum şartları maliyetli ve zaman isteyen bir süreç olup, bu süre ve maliyeti düşürmek için katalizör çalışmaları yapılması ve endüstriyel alanda fayda sağlanması planlanmaktadır. Son yıllarda amit bağı oluşumu için yapılan katalizör çalışmalarında yeterli ilginin sağlanmadığı görülmektedir. Son araştırmalar, sentetik ilaçların yaklaşık %25'inde amit bağlarının bulunduğunu göstermektedir. Bu nedenle, sentetik kimyacılar arasında, daha çevreci ve verimli amidasyon yöntemleri geliştirmek için yoğun bir çaba vardır. Alkol ve amin gibi bileşenlerden doğrudan amidasyon yöntemlerinin kullanımı, daha sürdürülebilir amit oluşum tepkimelerinin önünü açmaktadır. Günümüzde, artan antimikrobiyal direnç, yeni antimikrobiyal ajanların bulunmasını zorunlu kılmaktadır. Bakteriyemi ve sistemik mantar enfeksiyonları gibi sağlık sorunları ortaya çıkmaktadır. Ancak, mevcut tedavi seçenekleri sınırlı olup, patojenik bakterilerin çoklu antimikrobiyal ajanlara karşı direnç geliştirmesi, tedaviyi daha da zor hale getirmektedir. Bu nedenle, yeni ve etkili antimikrobiyal ajanların keşfi, halk sağlığı açısından kritik bir öneme sahiptir. Bu tez çalışmasında 5,6-dimetilbenzimidazolyum grubunun azot üzerinden farklı, hacimli ve fonksiyonel grup içiren aril grupları bağlanarak yeni karben öncülleri sentezlenmiştir. Hazırlanan yeni karben öncülleri Ru ve Ag bileşikleri ile etkileştirilerek yeni N-Heterosiklik karben kompleksleri hazırlanmıştır. Sentezlenen Ru-NHC kompleksleri amit bağ oluşum tepkimelerinde katalizör olarak kullanılmıştır. Ag-NHC kompleksleri ise antimikrobiyal aktiviteleri incelenmiştir.Öğe Heteroaromatik bileşiklerin arilasyonu(İnönü Üniversitesi, 2019) Evren, EnesEkonomik açıdan önemli sayılabilecek birçok farmasötik veya zirai kimyasal madde, vazgeçilemez alt yapılar olarak heteroaril birime sahip olduğundan, heteroaromatik bileşikler, biyoloji veya malzeme bilimleri gibi çeşitli alanlarda çok çeşitli uygulamaları içeren kapsamlı bir geçmişe sahip önemli yapısal birimlerdir. Heteroarenlerin aril halojenürlerle doğrudan arillenmesi modern organik sentezde C-C bağlarının oluşumu için en değerli yöntem haline gelmiştir. Aril halojenürler ve heteroarenler arasındaki doğrudan eşleşme, tepkime aşamalarının en aza indirilmesi ve yan ürün oluşumunun azaltılması açısından avantajlıdır. Son yıllarda, bu alandaki çok çeşitli çalışmalar yeni C-H bağ dönüşümlerinin gelişimine odaklanmıştır. Bu gelişmeden sonra, piroller, azoller, (benzo) tiyofenler ve (benzo) furanlar gibi diğer değerli heteroarenlerin doğrudan arillenmesi için çeşitli yöntemler geliştirilmiştir. N-heterosiklik karben (NHC) ligandları, elektronik ve sterik olarak kontrol edilebilir ve genellikle farklı metal iyonları ile termal olarak kararlı bileşikler oluştururlar. NHC ligandlarının güçlü σ-donör fakat zayıf π-alıcı özellikleri, birçok kararlı palladyum(II)-NHC kompleksinin oluşumunu da sağlamaktadır. Palladyum(II)-NHC kompleksleri aktivitesi, kararlılığı ve seçiciliği nedeniyle, çok sayıda doğrudan arilleme reaksiyonunda oldukça reaktif ve seçici katalizörler olarak yaygın şekilde kullanılmıştır. Bu amaçla tez kapsamında yeni karben öncülleri ve palladyum kompleksleri sentezlenerek heteroaromatik bileşiklerin arilasyonu tepkimelerindeki katalitik aktiviteleri incelenmiştir. Elde edilen bulgular üç alt basamakta toplanabilir: 1) Alkil halojenürler ile 1-(2-Etilhekzilbenzimidazol) kullanılarak benzimidazolyum tuzları (1a-1k) sentezlendi ve yapıları uygun spektroskopik yöntemler ile açıklandı. 2) Sentezlenen benzimidazolyum tuzları, PdCl2 ve Pd(OAc)2 ile uygun şartlarda etkileştirilerek Pd-NHC Kompleksleri sentezlendi ve yapıları aydınlatıldı (2a-2h ve 3a-3c) 3) Sentezlenen Pd-NHC komplekslerinin heteroaromatik bileşiklerin arilasyon tepkimesindeki katalitik aktiviteleri incelendi.Öğe Palladium-PEPPSI complexes: A robust and versatile catalyst system for the C-H arylation of heteroarenes(Elsevier, 2026) Evren, Enes; Gurbuz, Nevin; Ozdemir, IsmailIn this study, the catalytic activities of newly synthesized Pd-PEPPSI complexes, derived from benzimidazole ligands functionalized with phthalimide groups were investigated in the arylation reactions of heteroaromatic ketones. The covalently attached phthalimide unit on the benzimidazole ring significantly modified the electronic and steric properties of the NHC ligands, thereby enhancing the catalytic performance of the complexes. The synthesized Pd-NHC complexes were characterized by 1H and 13C NMR, FT-IR spectroscopy, and melting point determination. For catalytic applications, 2-acetylfuran and 2-acetylthiophene were selected as model substrates, and their cross-coupling (arylation) reactions with various aryl halides were carried out under an inert atmosphere (argon) using Potassium acetate (KOAc) as base and Dimethylacetamide (DMAc) as a solvent. Reaction parameters such as temperature and time were optimized. The Pd-PEPPSI complexes exhibited high conversion rates and excellent selectivity even at low catalyst loadings, predominantly yielding C5-arylated products. The electron-donating nature and conjugation effects of the heteroatoms (S and O) in the aromatic rings of 2-acetylthiophene and 2-acetylfuran were evaluated in terms of their interaction with the Pd center and their influence on substrate activation. Additionally, the position of the phthalimide group and the nature of substituents on the benzimidazole ring were comparatively assessed for their impact on catalytic performance. Overall, the results demonstrated that 1-(phthalimide)benzimidazole-based Pd-NHC complexes act as highly efficient, stable, and reusable catalysts for C-C bond-forming reactions, especially involving heteroaromatic substrates. Furthermore, the synthesized N-phthalimido benzimidazoles can be converted into various salts via reaction with different aryl or alkyl halides, potentially allowing for the synthesis of other metal-NHC complexes with different transition metals. Such derivatives may be explored for applications in catalysis, as well as in antimicrobial or anticancer research. These findings support the potential of these complexes in advanced organic synthesis and pharmaceutical chemistry.Öğe PEPPSI-type N-heterocyclic carbene palladium(II) complexes as catalysts in the direct C5 arylation of furan and thiophene(Elsevier Science Sa, 2025) Atakol, Arda; Yigit, Beyhan; Akdan, Hasan; Evren, Enes; Celepci, Duygu Barut; Yigit, Murat; Aygun, MuhittinIn this study, a series of amine-functionalized benzimidazolium salts and their PEPPSI-type N-heterocyclic carbene (NHC) palladium(II) complexes 3a-e were synthesized and characterized by FT-IR, 1H NMR and 13C NMR spectroscopy, elemental analysis, and mass spectrometry. The molecular and crystal structure of 3c and 3d was confirmed by the single-crystal X-ray diffraction (SC-XRD) method. Structural analysis reveals that the geometries of the PdII centers of the complexes adopt slightly distorted square planar environment. The new palladium complexes were tested as catalysts in the direct C5 arylation of 2-acetylfuran and 2-acetylthiophene with aryl bromides at 120 degrees C in N,N-dimethylacetamide. The arylation reactions proceeded selectively at the C5 position of the heteroaromatic compounds, and the corresponding coupling products were obtained in moderate to good yields by using 1 mol% of the palladium complex. Also, solid computational validation of the experimental results was achieved by geometric optimizations, frontier molecular orbital and molecular electrostatic potential studies, as well as natural bonding orbital analysis utilizing density functional theory.Öğe Plausible PEPPSI catalysts for direct C-H functionalization of furans and pyrroles(Elsevier, 2024) Munir, Naima; Gurbuz, Navin; Zafar, M. Naveed; Evren, Enes; Sen, Betul; Aygun, Muhittin; Ozdemir, IsmailThe worth of bi(hetero)arenes in ongoing medicinal and industrial research fields promotes their efficient synthesis by Pd-PEPPSI-bearing NHC spectator ligands encapsulated as site-selective direct C-H functionalization agents. Eight new asymmetric N-heterocyclic carbenes ligands and their plausible pyridine-assisted Pd (II) complexes are reported in this work. The synthesized compounds were thoroughly characterized by respective spectroscopic techniques, such as 1H, 13C, FTIR and elemental analysis. The structures of synthesized pro-ligand salts and complexes were determined by Single Crystal XRD. The on/off mechanism of pyridine assisted Pd-NHC complexes made them the best C-H functionalized catalysts for regioselective C5 arylated products. Five membered heterocyclic compounds such as 2-acetyl furan, furfuryl acetate and 1-methyl-2-pyrrole-carboxylaldehyde were treated with numerous aryl bromides under optimal catalytic reaction conditions. Furfuryl acetate was used for the first time as a substrate in the present research work. Interestingly, all the prepared catalysts possessed essential structural features that facilitated the formation of desired coupled products in quantitative yield with excellent selectivity.Öğe Rhodium(i) N-heterocyclic carbene complexes: synthesis and cytotoxic properties(Royal Soc Chemistry, 2021) Slimani, Ichraf; Sahin-Bolukbasi, Serap; Ulu, Mustafa; Evren, Enes; Gurbuz, Nevin; Ozdemir, Ilknur; Hamdi, NaceurRhodium(i) complexes bearing N-heterocyclic carbene (NHC) ligands have been widely used in catalytic chemistry, but there are very few reports of biological properties of these types of complexes. A series of benzimidazolium salts and their [RhCl(NHC)(COD)] complexes were synthesized. The obtained complexes were synthesized and characterized by elemental analysis, FT-IR, H-1 and C-13 NMR. All compounds were screened for in vitro cytotoxic activities against a panel of human cancer cells (HT-29 colon, Ishikawa endometrial, and U-87 glioblastoma) using the MTT assay for 48 h of incubation time. Mouse fibroblast cells (L-929) were used as healthy cells. Complexes had exhibited significantly higher cytotoxic activity towards cancer cells than their ligands and complex 2b showed the most selective cytotoxic activity against HT-29 cancer cells (SI;7.05) and Ishikawa cancer cells (SI; more than 9.8). The complexes showed strong in vitro cytotoxic activity against cancer cells, with IC50 values of lower than 10 mu M (except 2a against HT-29 (12.8 mu M) and 2b against U-87 (11.1 mu M)). All complexes (2a-d) showed the highest in vitro cytotoxic activity against Ishikawa endometrial cancer cells with IC50 values of 2.93 +/- 0.06, <1, 2.60 +/- 0.05, and 2.85 +/- 0.06 mu M, respectively. Complexes were found to be highly cytotoxic against HT-29, Ishikawa, and U-87 cancer cells compared to the anticancer agents, cisplatin and 5-FU.Öğe Ruthenium(II) complexes bearing N-heterocyclic carbene ligands with wingtip groups and their catalytic activity in the transfer hydrogenation of ketones(Elsevier Science Sa, 2020) Yigit, Beyhan; Isik, Yilmaz; Celepci, Duygu Barut; Evren, Enes; Yigit, Murat; Gurbuz, Nevin; Ozdemir, IsmailA series of new silver(I) complexes bearing N-heterocyclic carbene (NHC) ligands with wingtip groups were synthesized by the reaction of 1,3-dialkylimidazolinium salts with silver(I) oxide in dichloromethane. The silver complexes were used as carbene-transfer agents to synthesize ruthenium(II) complexes with the general formula [RuCl2(NHC)(eta(6)-p-cymene)]. All the synthesized complexes were characterized by elemental analysis, FT-IR, H-1 NMR and C-13 NMR spectroscopy, and the molecular and crystal structure of 3d was determined by single-crystal X-ray diffraction. These ruthenium complexes were tested as catalysts in the transfer hydrogenation of ketones using (PrOH)-Pr-i as a hydrogen source. All compounds tested showed good catalytic activity in these reactions.Öğe Ruthenium(II) p-cymene complexes bearing amine-functionalized N-heterocyclic carbenes: Synthesis, characterization, in silico and enzyme inhibition studies(Pergamon-Elsevier Science Ltd, 2025) Yigit, Beyhan; Erturk, Adem; Celepci, Duygu Barut; Akdan, Hasan; Evren, Enes; Taskin-Tok, Tugba; Yigit, MuratAlthough the ruthenium N-heterocyclic carbene (NHC) complexes have been widely used in catalysis, they have only recently been evaluated for medicinal applications. Herein, a series of new ruthenium(II) p-cymene complexes with benzimidazole-based NHC ligands were synthesized by the transmetalation reaction from silver(I)- NHC complexes. These complexes were characterized by FT-IR, 1H NMR and 13C NMR spectroscopy, elemental analysis, and mass spectrometry. Also, the molecular and crystal structures of 3f has been determined by the single-crystal X-ray diffraction method. Acetylcholinesterase (AChE) plays an important role in neurotransmission by hydrolyzing the neurotransmitter acetylcholine. On the other hand, carbonic anhydrase (CA) has a crucial role in living organisms for the maintenance of some obligatory metabolic functions. All the ruthenium(II) complexes were tested against the enzymes including AChE, hCAs I and II, which associated with epilepsy, glaucoma, and Alzheimer's disease (AD), respectively. These complexes 3a-f were recognized as highly potent inhibition effects towards hCA I isoenzyme (Kis: 2.80 f 0.05-35.46 f 9.07 mu M) and hCA II isoenzyme (Kis: 4.52 f 0.24-20.20 f 2.28 mu M) and AChE enzyme (Kis: 0.39 f 0.21-1.31 f 0.03 mu M). Besides these, molecular docking simulations and the ADMET process, which are computational methods, were used to elucidate and verify the results obtained from the above-mentioned studies at the molecular level.Öğe Substituted NHC-PEPPSI-Pd(ii) complexes: synthesis, characterization, DFT calculations and catalytic application in thiazole C-H arylation(Royal Soc Chemistry, 2026) Evren, Enes; Boubakri, Lamia; Zouaghi, Mohamed Oussama; Gurbuz, Nevin; Ozdemir, Ismail; Arfaoui, Youssef; Attour, AnisIn this study, a series of functionalized benzimidazolium salts and their PEPPSI-type Pd(ii)NHC complexes 3a-g were synthesized and characterized by FT-IR, 1H NMR and 13C NMR spectroscopy, elemental analysis, and mass spectrometry. Quantum chemistry computations at the B3LYP/6-311G(d,p)/LANL2DZ level were used to examine the molecular structure, electronic characteristics, and chemical reactivity of the ligand and its Pd complex. The new salt and PEPPSI-type Pd-NHC complex were fully characterized by spectroscopic and analytical methods. Under the optimized reaction conditions, the catalytic activity of the NHC-PEPPSI-Pd(ii) complexes was tested by direct arylation of 2-n-propylthiazole and 4,5-dimethylthiazole with various aryl halides at 120 degrees C for 1 h and 3 h, respectively. It was observed that the palladium complexes gave high yields and were selective at the C5 and C2-positions of heteroaryl derivatives. Complex 3f, with an NHC substituted by a 3,4,5-trimethoxybenzyl group, showed the highest conversion probably due to the flexibility, electronic and mostly steric effects of this group.Öğe Synthesis and in silico studies of Novel Ru(II) complexes of Schiff base derivatives of 3-[(4-amino-5-thioxo-1,2,4-triazole-3-yl)methyl]-2(3H)-benzoxazolone compounds as potent Glutathione S-transferase and Cholinesterases Inhibitor(Elsevier, 2021) Adiguzel, Ragip; Turkan, Fikret; Yildiko, Umit; Aras, Abdulmelik; Evren, Enes; Onkol, TijenNovel Ru(II) complexes of Shiff base derivatives of 3-[(4-amino-5-thioxo-1,2,4-triazole-3-yl)methyl]-2(3H)benzoxazolone were synthesized. The ligands (1a-e) were confirmed by IR, H-1 NMR, and C-13 NMR spectra (only 1b and 1c). Structures of the synthesized Ru(II) complexes (2a-e) were illuminated by elemental analysis, IR, H-1 NMR, C-13 NMR, and mass spectra. As the biological studies, the inhibitory potency of the ligands and the novel synthesized complexes were evaluated against the glutathione S-transferase (GST), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes in vitro conditions. Ki values in the range of 26.87-47.63 mu M for AChE, 23.51-42.81 mu M for BChE, and 33.14-51.73 mu M for GST, respectively. The free binding energy of most active inhibitors against AChE, BChE, and GST enzymes were detected as-10.183 kcal/mol, -9.111 kcal/mol, and -6.097 kcal/mol, respectively. All compounds docked were observed to bind in the active site of the enzymes with similar binding orientation and binding interactions with the surrounding amino acids. (C) 2021 Published by Elsevier B.V.Öğe Synthesis, characterization and antitumor properties of novel silver(I) and gold(I) N-heterocyclic carbene complexes(Elsevier Science Sa, 2020) Ozdemir, Ilknur; Ciftci, Osman; Evren, Enes; Gurbuz, Nevin; Kaloglu, Nazan; Turkmen, Nese Basak; Yasar, SeymaIn this study, two novel benzimidazolium salts consisting propane sulfonate order were integrated in high yields as N-heterocyclic carbene (NHC) precursors. The silver-NHC buildings were set up by responding 1-(2,2-dimethoxyahyl)-3-(propyl-3-sulfonate)benzimidazolium and 1-(2,2-diethoxyahyl)-3-(propyl-3-sulfonate)benzimidazolium with silver oxide on average state. Gold-NHC edifices were acquired by means of transmetallation of their silver precursors with [AuCl{S(CH3)(2)}]. The structures of all mixes were completely portrayed by spectroscopic techniques H-1 NMR, C-13{1H} NMR, IR and elemental and further analyzed by DFT/TDDFT strategies. IC50 values and cytotoxic impacts of these four complexes were controlled by the MTS put together examine with respect to three human cancer cell lines neuroblastoma (SHSY5Y), adenocarcinoma (HEP3B), and human fibroblasts (HF).Öğe Synthesis, characterization, and anticancer potential of novel NHC ligands and their selenium complexes: a combined in vitro and in silico investigation(Royal Soc Chemistry, 2025) Boualia, Boutheina; Sandeli, Abd el-Krim; Evren, Enes; Ozdemir, Ismail; Karci, Huseyin; Dundar, Muhammed; Ozdemir, IlknurWe report herein the efficient synthesis of new benzimidazolium salts (A1-A6) and their corresponding selenium-NHC complexes (B1-B6), along with the evaluation of their cytotoxicity profiles against two cancer cell lines (HCT116 and SH-SY5Y) and one normal cell line (BEAS-2B). The findings revealed that the benzimidazolium salts (A1-A6) exhibited significantly higher cytotoxicity toward all tested cell lines compared to their selenium derivatives (B1-B6). Among them, compounds A3, A4, and A5 showed the most potent cytotoxic effects, with IC50 values ranging from 3.09 to 26.12 mu M, approximately ten times lower than that of cisplatin. However, these compounds also exhibited relatively low IC50 values in normal BEAS-2B cells, although still higher than those observed in the cancer cell lines, indicating a preferential cytotoxicity toward cancer cells. Structure-activity relationship analysis revealed that the benzimidazolium core acts as the pharmacophore of these compounds, while substitution on the aromatic ring-particularly with bulky groups-enhances cytotoxicity. Conversely, incorporation of the selenium atom was found to markedly reduce or even eliminate cytotoxicity up to concentrations of 800 mu M. Further in silico studies were conducted to gain a deeper understanding of the molecular structures and chemical reactivity of these compounds. In addition, molecular docking studies against PARP-1 and tubulin highlighted the strong inhibitory potential of the most active compounds (A3, A4, and A5) toward both targets, suggesting their potential involvement in the observed cytotoxic effects. Overall, these investigations propose benzimidazolium salts A3, A4, and A5 as promising anticancer agents and highlight the selenium derivatives as non-toxic selenium-based NHC complexes. Further studies should be undertaken to optimize the biological activity of these compounds and to enhance their selectivity toward cancer cells.Öğe Synthesis, structures and catalytic activity of Pd(II) saccharinate complexes with monophosphines in direct arylation of five-membered heteroarenes with aryl bromides(Elsevier Science Sa, 2020) Yilmaz, Veysel T.; Icsel, Ceyda; Turgut, Omer R.; Aygun, Muhittin; Evren, Enes; Ozdemir, IsmailA number of new Pd(II) saccharinate (sac) complexes bearing a range of phenyl (Ph), cyclohexyl (Cy) and alkyl (Me and Et) substituted tertiary phosphine ligands with systematically changing electronic and steric properties, namely trans-[PdCl(sac)(L)(2)] (L = PPh3 (1); PPh2Cy (3)), trans-[Pd(sac)(2)(H2O)(L)] (L = PPh3 (2); PPh2Cy (5)), trans-[Pd(sac)(2)(L)(2)] (L = PPh2Cy (4); PPhCy2 (6); PCy3 (8)), [PdCl(sac)(PCy3)(DMSO)] (7), trans-[Pd (sac)(2)(PPh2Me)(DMSO)] (9) and cis-[M(sac)(2)(L)(2)] (L= PPhMe2 (10); PPh2Et (11); PPhEt2 (12)), were synthesized and structurally characterized. The Pd(II) complexes were applied for direct C2/C5 arylation of fivemembered heteroarenes such as furan, thiophene and thiazole derivatives with aryl bromides. Notably, arylation products up to 99% yields were obtained in the presence of the Pd(II) complexes. The catalytic mechanism of the direct arylation was proposed to proceed via a Pd(0)/Pd(II) pathway, due to elimination of the sac ligand in the Pd(II) complexes during catalysis.Öğe Systematic study on the catalytic performance of NHC-ligated silver(I) complexes(Elsevier Science Sa, 2026) Akkoc, Mitat; Onder, Belgin; Evren, Enes; Karaca, Emine Ozge; Gurbuz, Nevin; Ozdemir, IsmailThis study reports the synthesis of novel N-heterocyclic carbene (NHC) ligated silver(I) complexes, which are gaining increasing attention as versatile catalysts in organic synthesis. The structural properties of the synthesized compounds were elucidated in detail using various spectroscopic and thermal analysis techniques, including FTIR, NMR spectroscopy, and melting point determination. These analyses confirmed the successful formation of the complexes and verified that they exhibited the expected molecular structures. The low cost and unique chemical properties of silver make it an attractive alternative to other transition metals. In this context, the catalytic potential of the synthesized Ag-NHC complexes was investigated in the A3 coupling reaction, a key method for the synthesis of propargylamines. The A3 reaction is a crucial step in the formation of nitrogencontaining compounds of significant importance in pharmaceutical and natural product chemistry. Experimental results demonstrated that the Ag-NHC complexes effectively catalyzed the reaction, leading to high yields. In conclusion, this research successfully achieved the synthesis and characterization of new Ag-NHC complexes. Following the acquisition of structural analysis data, their catalytic activity in the A3 coupling reaction was successfully investigated.Öğe Yeni Metal-Nhc Komplekslerinin Sentezi, Katalitik Ve Biyolojik Uygulamaları(2023) Ozdemır, Ilknur; Koc, Ahmet; Yaşar, Sedat; Uçar, Ayşegül; Evren, Enes; Özdemir, İsmail; Gürbüz, NevinAmit bağı tartışmasız kimyadaki en önemli bağlardan biridir. Enzimler gibi, proteinlerdeki peptid bağlarını oluşturarak yaşamın sürdürülmesinde gereklidir ve aynı zamanda farmasötik moleküller, zirai kimyasallar ve doğal ürünlerdeki en önemli fonksiyonel gruplardan biridir. Bu nedenle, hızlı ve yüksek verimli, yüksek atom ekonomili amidasyon yöntemleri sentez kimyacıları için zorunlu bir bilimsel arayış haline gelmiştir. Aslında, alkoller ve aminlerden doğrudan amidasyon tepkimeleri, daha çevreci amit oluşum reaksiyonlarının geliştirilmesinde kilit bir rol oynar. Rutenyum komplekslerinin, amit oluşum reaksiyonunda etkili katalizörler olarak kullanılması son zamanlarda ilgi ile çalışılmaktadır. NHC ligandlarının kararlı olmaları NHC ligandı taşıyan metal komplekslerinin termal ve oksidatif kararlılıklarında artış meydana getirmektedir. Bu nedenle tepkime ortamında uzun ömürlü ve oldukça aktif katalizörler oluşmaktadır. Bilindiği gibi ligandların özellikleri, metal komplekslerinin biyoaktivitelerinde önemli bir rol oynar. Bunlar arasında, N-heterosiklik karben (NHC) ligandlarının metal kompleksleri sonyıllarda ümit verici sonuçlar göstermiştir. Ag(I)-NHC'ler, metal-NHC'ler arasında en çok sentezlenen ve çalışılan bileşiklerdir. Son on yılda, Ag(I) -NHC kompleksleri, insanlarda düşük toksiditeleri ve gümüşün daha yavaş salınması nedeniyle uzun süreli biyolojik aktiviteye yol açan geliştirilmiş antibakteriyel maddeler olarak ortaya çıkmıştır. Bu amaçla; projede 20 adet yeni 5,6-dimetilbenzimidazol (I) karben öncülleri sentezlenerek yapıları uygun spektroskopik yöntemlerle aydınlatıldı. Benzimidazolyum tuzlarının (I) [RuCl2(p-simen)]2 ile etekileştirilmesiyle yeni 14 adet Ru-NHC kompleksi (II ve III), Ag2O ile etekileştirilmesiyle yeni 20 adet Ag-NHC kompleksi (IV) hazırlandı ve yapıları uygun spektroskopik yöntemlerle aydınlatıldı. Hazırlanan rutenyum-karben komplekslerinin, alkoller ve aminlerden doğrudan amidasyon tepkimelerindeki katalitik aktiviteleri incelendi ve bunların belirtilen tepkimelerde aktif katalizörler olduğu görüldü. Benzimidazolyum tuzlarının ve Ag-karben komplekslerinin BMD (Broth Microdilution) yöntemi kullanılarak Gram-negatif (E.coli and P.aeruginosa), Gram-pozitif (S.aureus) ve fungal (C.albicans, C.glabrata) bakteri suşlarına karşı antimikrobiyal aktivteleri incelendi.
